export {}
// 类型别名
let state1: number | string | boolean = 1
let state2: number | string | boolean = 'abc'
let state3: number | string | boolean = false

// 类型太长，容易出错
type MyType = number | string | boolean
let state4: MyType = 2
let state5: MyType = '2'
let state6: MyType = false

// state6 = [] // 不行的